Optimum accessories for the photometric quantities to be measured
Instrument Systems offers a series of EOPs for measuring irradiance and universal radiation coupling. These differ mainly in terms of light throughput, degree of cosine correction and spectral range. All EOP optical probes contain a diffusor for scattering incident light. Behind the diffusor is the entrance facet of the optical fiber, with which light is coupled into the spectrometer.
Applications
For general applications we recommend optical probes EOP 120 and EOP 121 (lateral fiber bundle connector), as these offer the best compromise between good cosine correction and good light throughput.
Good to very good cosine correction is needed to measure extended light sources, although this is always at the expense of light throughput. Optical probe EOP-146 is the right choice for this purpose.
Optical probe EOP 140 is only suitable for applications requiring high light throughput. Model EOP 542 is available for measurements with a fixed field-of-view (5.7°) and is primarily used for measuring direct sunlight.
Instrument Systems offers integrating sphere ISP 40 for optimum cosine correction with a wide spectral range. Due to the integrating effect of the sphere, the entire beam is captured regardless of its convergence or divergence and coupled via the fiber bundle with the spectrometer.